相关疑难解决方法(0)

我试图将视图控制器向下转换为详细视图控制器但不能.我正在使用核心数据(第一次).错误在prepareForSegue方法中,并显示:"无法将类型'UIViewController'(0x1b81cdc)的值转换为'Patternz.PatternDetailViewController'(0x32488).(lldb)"

希望解释为什么它不起作用.这是文件.

ViewController.swift

import UIKit
import CoreData

class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {

    @IBOutlet weak var tableView: UITableView!

    var patterns : [Pattern] = []

    var selectedPattern : Pattern? = nil


    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        self.tableView.dataSource = self
        self.tableView.delegate = self

        createTestPatterns()

        var context = (UIApplication.sharedApplication().delegate as! AppDelegate).managedObjectContext!

        var request = NSFetchRequest(entityName: "Pattern")

        var results = context.executeFetchRequest(request, error: nil)

        if results != nil {
            self.patterns = results! …